textproduct: Quad Cities

SHORT TERM /THROUGH SATURDAY NIGHT/

Issued at 152 PM CDT Fri Sep 11 2026

While temperatures have not felt much like fall is of yet, this morning's fog event sure looked like it! Late night fog development in our southern counties advected and spread northwest to reach nearly up to Iowa City and Cedar Rapids before dissipation won out by 10 AM. by late morning, with southerly winds remaining under 12 kts. This is certainly a problem more associated with cool season long nights and long lasting morning inversions. Anyhow, the fog has now lifted into a shallow cumulus/stratus field over far eastern Iowa and far western Illinois. This should gradually dissipate the rest of the afternoon, with sunshine lasting through sunset, along with pleasant temperatures in the lower 80s, and moderate humidity.

Tonight, initially clear skies will begin to cloud up from west to east overnight, as WAA begins aloft. Most guidance is dry for tonight, but there is enough signal for a few showers and thunderstorms in our western counties after midnight to keep the 20% pops going, along with spotty light QPF. This activity, should it occur, will linger into Saturday morning, mainly south of Highway 34 in southeast IA, and northeast MO. No severe weather or strong storm threats are expected.

Saturday remains a mainly dry day for our region, with the baroclinic zone aloft mainly southwest of our CWA. Some isolated showers/storms are possible in our far southwestern counties near that elevated boundary south of us, but the majority of our counties are expected to remain dry through Saturday evening. Pops in the south are only 10-20% for this low chance.

SHORT TERM /THROUGH SATURDAY NIGHT/

Issued at 612 PM CDT Fri Sep 11 2026

While temperatures have not felt much like fall is of yet, this morning's fog event sure looked like it! Late night fog development in our southern counties advected and spread northwest to reach nearly up to Iowa City and Cedar Rapids before dissipation won out by 10 AM. by late morning, with southerly winds remaining under 12 kts. This is certainly a problem more associated with cool season long nights and long lasting morning inversions. Anyhow, the fog has now lifted into a shallow cumulus/stratus field over far eastern Iowa and far western Illinois. This should gradually dissipate the rest of the afternoon, with sunshine lasting through sunset, along with pleasant temperatures in the lower 80s, and moderate humidity.

Tonight, initially clear skies will begin to cloud up from west to east overnight, as WAA begins aloft. Most guidance is dry for tonight, but there is enough signal for a few showers and thunderstorms in our western counties after midnight to keep the 20% pops going, along with spotty light QPF. This activity, should it occur, will linger into Saturday morning, mainly south of Highway 34 in southeast IA, and northeast MO. No severe weather or strong storm threats are expected.

Saturday remains a mainly dry day for our region, with the baroclinic zone aloft mainly southwest of our CWA. Some isolated showers/storms are possible in our far southwestern counties near that elevated boundary south of us, but the majority of our counties are expected to remain dry through Saturday evening. Pops in the south are only 10-20% for this low chance.

LONG TERM /SUNDAY THROUGH FRIDAY/

Issued at 152 PM CDT Fri Sep 11 2026

By Sunday, there is broad support for shifting the surface and elevated boundaries focusing the storms, much closer to our CWA. This will begin a long duration of rain and thunderstorms near our latitude. Initially, instability is questionable though Sunday, with the main boundary still southwest of eastern Iowa. This seems to be reflected in 40-70 percent pops, by Sunday afternoon and evening, with relatively light QPF under 0.20".

Of particular note in this active period is the Monday shortwave. Latest guidance has this wave trending slower, resulting in the initial warm front not reaching the area until Monday afternoon. This has lead to a decreasing trend in high temperatures for Monday, though highs are still expected to be above-normal due to the strong warm advection regime. This will also establish instability across the warm sector supportive of showers and thunderstorms. Guidance also suggests that vertical shear will be near 40-50 kts and thus allow for organized convection. This is most likely with forcing along a descending cold front, though uncertainty with timing makes it unclear whether this threat would be in the daytime or overnight hours.

As this frontal boundary passes through the area, it is expected to stall across the region. While there is some uncertainty in where exactly this boundary will set up, current guidance suggests it will be along our south. This then provides the focus for rainfall over the next several days, especially as southwesterly flow provides a continuous stream of moisture. Additional waves towards the latter half of the period will help push this boundary out of the region, though chances for rain will remain. The near daily rainfall potential, offers a growing threat for heavy rainfall, and a rather widespread chance for 2-4 inches is growing in the region. If this sets up over recent wet counties, a flood threat could develop.

AVIATION /00Z TAFS THROUGH 00Z SATURDAY/

Issued at 612 PM CDT Fri Sep 11 2026

VFR conditions will prevail through much, if not all, of the TAF period. There will be the chance for an MVFR/IFR stratus deck to move through between 12-18z from northwest to southeast, but confidence is low on this right now. Opted to include a scattered deck around 2000 ft at this time for CID/DBQ. Otherwise, we will have shifting winds through the day Saturday. Winds will start the TAF period light and out of the south, with a cold front passing through Saturday shifting winds northwesterly around 10 KTs.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.